【单选题】听力原文:W: What would you do if you were in my place? M: If Paul were my son,I'd just not worry. Now that his teacher is giving him extra help and he's working hard himself. he's sure to do well in the n...
【简答题】许多人预测自然资源的价格相对于其他物品的价格应该保持持续上涨,因为随着世界人口的增长,对自然资源的需求在持续增加,其需求曲线不断向右上方移动,而自然资源是一种可耗竭资源,随着资源的日益枯竭其供给曲线将不断向左上方移动。然而,大多数自然资源的相对价格并没有上涨,相反,恰如美国经济学家朱利安·L·西蒙(Julian L. Simon)和生态学家保罗·R·埃利希(Paul R. Ehrlich)的“世纪...